Coated articles are known in the art for use in window applications such as insulating glass (IG) window units, vehicle windows, monolithic windows, and/or the like. In certain example instances, designers of coated articles often strive for a combination of high visible transmission, low emissivity (or low emittance), and/or low sheet resistance (Rs). High visible transmission may permit coated articles to be used in applications where these characteristics are desired such as, for example, in architectural or vehicle window applications, whereas low-emissivity (low-E), and low sheet resistance characteristics permit such coated articles to block significant amounts of IR radiation so as to reduce for example undesirable heating of vehicle or building interiors. Thus, typically, for coatings used on architectural glass to block significant amounts of IR radiation, high transmission in the visible spectrum is often desired. However, low transmittance and/or high reflectance in the IR and/or near IR part(s) of the spectrum are also desired to reduce for example undesirable heating of vehicle or building interiors.
In certain example embodiments, an overcoat may be provided over a low-E coating or the like in order to increase durability. However, in some instances, these overcoats may experience stress as-deposited, or may experience stress upon being heated, during heat treating, heat bending, thermal tempering, and the like. In certain cases, the stress from these overcoats may negatively affect the overall durability of the coating. Therefore, it may sometimes be desirable to provide a window unit or other glass article with a more durable overcoat.
In view of the above, it will be appreciated that there exists a need in the art for a layer and/or overcoat that may be incorporated into and/or over a low-E stack in order to increase the overall durability of the coated article. Certain example embodiments of this invention relate to a coated article that is durable, has an increased thermal stability, and has a reduced effect on optical characteristics. Certain example embodiments of this invention also relate to a method of making the same.
Certain example embodiments of this invention relate to a coated article comprising a substrate supporting a multi-layer coating on a major surface thereof. The coating comprises a low-E coating and a layer comprising gadolinium (Gd)-doped zirconium oxide over and possibly contacting the low-E coating. The low-E coating comprises, moving away from the substrate: a first dielectric layer, an IR reflecting layer comprising silver, and a second dielectric layer. The layer comprising Gd-doped zirconium oxide includes from about 1 to 20% Gd.
Certain example embodiments of this invention relate to a coated article comprising a functional coating provided on a major surface of a glass substrate. An overcoat layer is provided over the functional coating and/or as the outermost layer of the functional coating. The overcoat layer comprises gadolinium (Gd)-doped zirconium oxide.
According to certain example embodiments, the coated article is heat treated together with the coating. According to certain example embodiments, the coating has a net compressive residual stress following heat treatment and has a reduced tensile stress compared to a coating lacking Gd in the layer comprising Gd-doped zirconium oxide. According to certain example embodiments, the overcoat layer goes through fewer phase changes during the heat treating compared to an overcoat layer lacking Gd.
Certain example embodiments of this invention relate to a method of making a coated article including a coating supported by a glass substrate. A first dielectric layer is disposed, directly or indirectly, on the glass substrate. An IR reflecting layer is disposed over the first dielectric layer. A second dielectric layer is disposed over the IR reflecting layer. An overcoat layer comprising gadolinium (Gd)-doped zirconium oxide is sputter-deposited over the second dielectric layer, with the overcoat layer being the outermost layer of the coating. The glass substrate is heat-treated with the coating thereon. The overcoat layer comprises from about 1 to 20% Gd.
Certain example embodiments of this invention relate to a method of making a coated article including a coating supported by a glass substrate. The glass substrate is provided. A functional layer is disposed, directly or indirectly, on the glass substrate, with the functional layer being an IR reflecting layer. An overcoat layer comprising gadolinium (Gd)-doped zirconium oxide is sputter-deposited over the second dielectric layer, with the overcoat layer being the outermost layer of the coating and comprising from about 1 to 20% Gd. The glass substrate is heat treatable with the coating thereon. The coating has a net compressive residual stress and a reduced tensile stress compared to a coating lacking Gd in the overcoat layer.
The features, aspects, advantages, and example embodiments described herein may be combined to realize yet further embodiments.